US4789288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-cross threading screw
Assignee: Illinois Tool Works Inc
•
Filing: 1987-04-02
•
Granted: 1988-12-06
•
Expires: 2007-04-02
Abstract
Abstract A screw having a tapered and offset tip with a partial thread prevents cross-threading of the screw when inserted into a nut. The offset tip is a section of a conical frustum. The axis of the conical frustum section is offset from the axis of the shank of the screw. The conical frustum section is defined by those portions of a conical frustum contained within the outer radius of the screw shank. The partial thread is located on the side of the tip facing the direction of offset of the tip.
Inventors
- 👤 Francis C. Peterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:21
CPC Classifications
F; F16; F16B; F16B35/00; F16B35/04; F16B35/041; F16B35/044; F16B35/047
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
59 words
A screw, comprising: a head; a threaded shank projecting from said head, said shank having a tip at its axial end opposite said head, said tip comprising a section of a circular substantially conical frustum having a central axis which is offset from the central axis of said shank, said offset facing side having a partial thread formed thereon.
Claim 2
Dependent Claim
59 words
A screw, comprising: a head; a threaded shank projecting from said head, said shank having a tip at its axial end opposite said head, said tip comprising a section of a circular substantially conical frustum having a central axis which is offset from the central axis of said shank, said offset facing side having a partial thread formed thereon.
Claim 3
Dependent Claim
25 words
A screw in accordance with claim 1 wherein said section of a circular substantially conical frustum comprises a section of a right circular conical frustum.
Claim 4
Dependent Claim
45 words
A screw for preventing cross-threading, comprising: a head; and a cylindrical threaded shank projecting from said head, said shank having at its end opposite said head a circular substantially frusto-conical section having a central axis which is offset from the longitudinal axis of said shank.
Claim 5
Dependent Claim
45 words
A screw for preventing cross-threading, comprising: a head; and a cylindrical threaded shank projecting from said head, said shank having at its end opposite said head a circular substantially frusto-conical section having a central axis which is offset from the longitudinal axis of said shank.
Claim 6
Dependent Claim
27 words
A screw in accordance with claim 3 wherein said frusto-conical section is partially threaded on the side of said frusto-conical section facing the direction of said offset.
Claim 7
Dependent Claim
39 words
A screw in accordance with claim 3 wherein the centerpoint of said frusto-conical section is offset from the longitudinal axis of said shank by a distance equal to between 2 and 45 percent of the diameter of said shank.
Claim 8
Dependent Claim
41 words
A screw in accordance with claim 3 wherein the centerpoint of said frusto-conical section is offset from the longitudinal axis of said shank by a distance equal to between about 10 to about 20 percent of the diameter of said shank.
Claim 9
Dependent Claim
15 words
A screw in accordance with claim 4 wherein said partial threading comprises three partial threads.
Claim 10
Dependent Claim
102 words
A screw in accordance with claim 7 wherein said three partial threads comprise: a first partial thread located adjacent the end of said end having a circumferential length equal to between 4 and 20 percent of the circumferential length of said shank; and a second partial thread located adjacent said first partial thread and having a circumferential length equal to between 10 and 40 percent of the circumferential length of said shank; and a third partial thread located adjacent said second partial thread and having a circumferential length equal to between 20 and 70 percent of the circumferential length of said shank.
Claim 11
Dependent Claim
62 words
A screw for preventing cross-threading, comprising: a head; and a cylindrical threaded shank projecting from said head, said shank having at its end a partially threaded circular frusto-conical section, the centerpoint of said frusto-conical section being offset from the longitudinal axis of said shank by a distance equal to between about 10 to about 20 percent of the diameter of said shank.
Claim 12
Dependent Claim
62 words
A screw for preventing cross-threading, comprising: a head; and a cylindrical threaded shank projecting from said head, said shank having at its end a partially threaded circular frusto-conical section, the centerpoint of said frusto-conical section being offset from the longitudinal axis of said shank by a distance equal to between about 10 to about 20 percent of the diameter of said shank.
References Cited (Backward Citations)
US126366A
Cited
GB484671A
Cited
US3438299A
Cited
US3724315A
Cited
DE2913482A1
Cited
US4486135A
Cited
GB2127927A
Cited
US4534690A
Cited
US4630985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-12-06 | 1992-06-06 | 1992-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-06 | 1996-06-06 | 1996-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-06 | 2000-06-06 | 2000-12-06 | $7700.00 | Window Closed / Lapsed |